Eine Zukunftsaufgabe in guten HändenA future task in good hands

Floodplains in GermanySynergies with nature conservation, WFD and flood protection

BfN II 3.2 „Inland water, floodplain ecosystems and water balance“

Dr. Stephanie Natho

Foto: Thomas EhlertFoto: T. Ehlert

• is the scientific authority for national and

international nature conservation and landscape

management (Bonn – Leipzig – isle of Vilm)

• provides the scientific basis for political decisions

with respect to nature conservation

• cooperates with the authorities of the federal

states

• is one of the research agencies of the German

Ministry of Environment

Who we are…

30 river and floodplain

projects (1979-2013)

App. 60,000 ha of the core

areas of Large Scale

Conservation projects lie

within the boundaries of

floodplains

Total funding:

278.5 mill. € (1979-2013)

Foto: A. Krause

River/floodplain

projects

others

Sources: Federal Agency for Nature Conservation (BfN), 2013

Geobasisdata ©GeoBasis-DE/BKG 2011

Large Scale

Conservation Projects

How to map the status of

floodplains?

Status of FloodplainsStructural Quality ofsurface water bodies

Ecological Status ofsurface water bodies

Source: UBA according to LAWA 2002

?

Source: BMU/UBA 2010, according to Portal

Wasserblick/BfG, last update March 22 2010

Source: BfN 2009

Floodplains – loss of naturalness

near natural <1%

slightly modfied 9%

moderately modified

36%

severely modified

34%

totally modified

20%

near natural

slightly modified

moderately modified

severely modified

totally modified

Status report of

German floodplains

www.bfn.de/0324_auenzustandsbericht.html

BfN 2009

Floodplains – loss of inundation area

Status

report of

German

floodplains

BfN 2009

www.bfn.de/0324_auenzustandsbericht.html

• 15,000 km² of floodplains

(4.4 % of Germany)

• Losses of 2/3 of

floodplains available for

inundation on the basis of

a HQ100

• At large rivers (Elbe,

Rhine, Danube) losses of

up to 90%

• BUT lower losses do not

necessarily mean a

better status!

Loss of inundation areas

Bernd Neukirchen, 26.9.2011

Inundated dyked floodplain along the Elbe in the vicinity of

Wittenberg (Sachsen-Anhalt) 2002, Dam failure Seegrehna

Foto: A. Künzelmann

Active floodplain

Dyked floodplain

Legitimations: Long way to go…

2002: EU-WFD: good ecological status till 2015

2005: Amendment Act for the improvement of a preventive flood

control: including e.g. introduction of „inundation areas“ for flood

water retention to the Federal Water Act

2007: EU-Floods Directive: Floodrisk management plans with focus on

prevention: give rivers more space!

2007: National Strategy on Biological Diversity: increase of active

floodplains by 10% till 2020

2009: Amendment to the Federal Water Act: Implementation of Floods

Directive

2011: EU Strategy on Biodiversity: Restoration of 15% of degraded

ecosystems with high priority to floodplains

2013: Coalition agreement: give rivers more space!

2015: ………

2020: ………

Foto: S. Natho

Foto: J. Purps

Foto: S. Natho

Foto: S. Natho

Floodplain Restoration Projects in

Germany

Dyke relocation Lenzen (2009)

Mittlere Elbe: Dyke relocation

Lödderitzer Forst (under

construction)

Restoration Lippe Aue (several

projects – partly finished/under

construction)

Mire Kieve (under construction)

• 146 projects

• 37 with dyke relocations

• Check for 91: effect on floodplain status

Floodplain restoration with

dyke relocation

The size of symbols represents the extent of the project

Floodplain

restoration

Foto: J. Purps

Examples of positive effects of

floodplain restoration projects

Lenzener Elbtalaue

Foto: K. Nabel

1999

2011Status of the floodplain after

implementation

• Status of floodplains

• FFH habitat types

• Biodiversity

• Recreation (Elberadweg)

• Nutrient retention

• Natural flooding/flood

control

• Dyke relocation (slotting old

dyke finished in 2009)

• 420 ha

• Initial planting of floodplain

forest

• Creation of side channels

Near natural

Slightly modified

Moderately modified

Severely modified

Totally modified

Floodplain status

Status of the floodplain before

implementation

Floodplain restoration and Flood

protection

Beispiel: Deichrückverlegung Lenzener Elbtalaue

Beseitigung einer Engstelle und

damit konstruktiven Schwachstelle

im Deichsystem

420 ha wiedergewonnene

Retentionsfläche / Aue

1/3 des Elbe-Abflusses fließen bei

Hochwasser über das Vorland

Durch die Deichrückverlegung (Fertigstellung 2009)

waren die Wasserstände 2011 im Gebiet wie

berechnet um 35 cm niedriger als bei vergleichbaren

Hochwassern vorher.

An der rd. 5 km elbaufwärts gelegenen Stadt

Schnackenburg sank der Hochwasserscheitel durch

die Deichrückverlegung um mehr als 20 cm.

Die positiven Auswirkungen der Deichrückverlegung

wurden auch beim Juni-Hochwasser 2013 festgestellt.

Quellen: LUGV Brandenburg / Alexy u. Faulhaber (2011), Damm / BfG (unveröff.)

Source: M. Hatz, BfG - Presentation IKSE on 21.11.2013D

yke

relo

cation

Reduction

45 cm

Effects on ca. 30 km

Economic value of floodplain

restoration

-20

-10

0

10

20

30 3D-Säule 1

3D-Säule 2

3D-Säule 3

3D-Säule 4

Zahlungs-bereitschaft

Annual cost and benefits in EUR (maximum scenario dyke relocation)

Investment dyke relocation,

agricultural losses of productivity

Avoided damages by floods

Savings for dyke maintenance

Nutrient retention

Willingness

to pay

Cost-Benefit-ratio 1:3incl. ecosystem services and payment

for biodiversity

Source: Grossmann et. al 2010

Scenario:

Dyke relocation for regaining

35,000 ha of floodplains

along the Elbe

Examples of positive effects of

floodplain restoration projects

• Flagship: combination of

nature conservation and

flood protection

• Dyke relocation

• 600 ha

Source: Pflege- und Entwicklungsplan

Planungsbüro Dr. Reichhoff, 2005

HQ2

Fotos: B. Neukirchen

Mittlere Elbe:Lödderitzer ForstRelocated dyke

Slotting of old dyke

• Status of floodplains

• FFH habitat types

• Biodiversity

• Nutrient retention

• Natural flooding/flood

controlSource: Pflege- und Entwicklungsplan

Planungsbüro Dr. Reichhoff, 2005

Old, partly slotted dykes

Current dyke

Relocated dyke

Cross sections with water level

Inundation heigths [m]

dry

Thanks to Joachim Drüke for his support for pictures.

ca. 2010

1993

Source: www.tim-online.nrw.de

Source: www.tim-online.nrw.de

Lippe Klostermersch

Examples of positive effects of

floodplain restoration projects

Status of the floodplain

before implementation

• Status of floodplains

• Structural water quality (WFD)

• Biodiversity/FFH habitats

• Leisure activities/recreation

• Natural flooding

Near natural

Slightly modified

Moderately modified

Severely modified

Totally modified

Status of the floodplain

after implementation

Source: http://www.lippetal.de/tourismus_freizeit/tourismus/radfahren/auenland.php

Floodplain status

• Removal of bank dykes

• Broadening/raising river bed

• 130 ha

• Channel restoration

• Change of landuse

Evaluation of Ecosystem Services -

nutrient retention in active floodplains

The sum of inundated

floodplains in Germany

retain up to

42,000 t nitrogen and

1,200 t phosphorus

– per year.

This equals a purification

service of 500 Mill. € per

year.

Source: Scholz et al. (2012)

Foto: S. Natho

Foto: S. Natho

Source: according to Schopp-Guth 1999

Fens

Bogs

Peatlands in Germany:

~ 5% of land area

~ 95% drained

~ 4 % of annual GHG emissions

Examples of projects:

ES-Benefits Reference scenario Project scenario

GHG emissions 1,300 t CO2-eq/a 530 t CO2-eq/a

Water quality 1.1 t N/a 0.3 t N/a

Local cooling 0 W 1,820 kW

Peatland biodiversity new habitats for peatland species

Groundwater recharge reserves enlarged by 150,000 m³

Project area:

Polder Kieve

65 ha, drained fen

Market-based instrument:

MoorFutures

GHG-Red. certification

50 years project lifetime

35 € per MoorFuture

(~1 t CO2-eq)

Project area

moderately moist intensive

grassland

wet reeds

very moist reed

moist /meadows

Reference scenario Project scenario

Source: C. Tegetmeyer

www.moorfutures.de

www.bfn.de

Concluding remarks

Several floodplain restoration projects carried out in

Germany – including 37 dyke relocation projects

Carrying out a floodplain status inventory before and after

implementation allows aggregated evaluation of success

(morphodynamics, hydrodynamics, vegetation & landuse)

Floodplain restoration results in multiple benefits for society

namely nature conservation (biodiversity, FFH etc.), flood

control, nutrient retention, carbon storage, WFD, recreation

But to reach aims of WFD, FFH, more funds are needed

New chances for floodplain restoration projects according to

the coalition agreement 2013:

a) national flood protection program with dyke relocations as

one measure

b) „Blaues Band“ to create a network of floodplain

restoration networks along federal water ways (out of use)

Foto: B. Neukirchen

Foto: J. Purps

Source: www.tim-online.nrw.de

Further reading

Cost-Efficiency

http://www.bfn.de/fileadmin/MDB/documents/themen/biologischevielfalt/Klimaseite/26.06.rivers-

10.45Dehnhardt.pdf

https://www.landschaftsoekonomie.tu-

berlin.de/fileadmin/a0731/uploads/publikationen/workingpapers/wp01104.pdf

Lippe:

http://www.bfn.de/fileadmin/MDB/documents/themen/landschaftsundbiotopschutz/Tagung_2008/Zimball_Lu

eneburg_2008.pdf

http://www.hamm.de/en/lifeplus-projekt.html

Havel and Elbe

http://www.climatebuffer.eu/visits/elbe-havel-rivers/elbe-river/index.html

BfN: Large Scale Conservation Projects:

http://www.bfn.de/0203_mittlere_elbe+M5054de7a952.html

http://www.bfn.de/0203_lenzen+M52087573ab0.html

Thanks for your attention